Jcampbell3

but if the radar has never been changed from the factory setting I would think that putting the alignment back to straight would improve the setting ND PERFORMANCE of the radar. It makes no sense to me that the radar performance follows the misalignment between the two. It’s more ov a PYA on their part. Mine works fine no error codes etc.thanks for the reply.

SMac770

There's no absolute in an alignment; it's all a bunch of variables that only have to be within a spec range. I could set all my toes a bit left and the car will drive "straight" but tilted (thrust angle off from absolute 0). So maybe the car was slightly thrust left and now it's slightly thrust right. But still "within spec". It doesn't seem to have been an issue for you this time, ok. But a corporation cannot write procedures based on "that one time that everything just seemed to work out". There is a legit scenario of errant operation following an alignment, and the only process to ensure that is not the case is to follow the alignment with a calibration. Also part of the reason I'm happy to not have a B9. All the assistance systems that need recalibration, alignments are $600 jobs now, and pretty much only the dealership is likely to have all the necessary toys.

Jcampbell3

I still don't' believe that the "radar alignment" follows an "out of wheel alignment" how would that happen? there is no linkage that i am aware of unless of course it's been hit or otherwise damaged. so regardless, you can do whatever you want to the alignment, but unless the radars alignment has changed you are only improving the vehicles tracking and hence the radars inherent alignment. yyou would certainly know from the ACC if that was the case. I just can't get my head around anything other than the above. paying 6-800 bucks would be my last alternative and
i would need evidence that the radar unit had moved and need adjustment.

cheers

SMac770

The radar unit is fixed to the lock carrier, it's not "moving". So if the angle the car points down the road shifts, the thrust angle, the radar unit is no longer looking in the same absolute direction. I don't think you're grasping what thrust angle is. The same recalibration is necessary, so they say, if you dismount the lock carrier (service position), which really sucks. There's no guarantee the lock carrier will sit just the same when you resecure it (really surprised how much play there is in how the lock carrier can be resecured).

Jcampbell3

Oh I fully understand what thrust angle is, have seen it on many pickups “crabing their way down the highway” over my 70 years. What you are not understanding is if the radar carrier has not moved from the factory any improvements made to a general 4 wheel alignment only makes things much better. It simple physics. In my case the alignment was off and the thrust angle slightly out in the rear, that does not automatically mean a realignment of the fixed radar housing. It makes no sense at all.